SAE AMS6419G

This specification covers a premium aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock.

These products have been used typically for parts, 3.5 inches (89 mm) and under in nominal section thickness, requiring a through-hardening steel capable of developing a minimum hardness of 53 HRC, the parts being subject to very rigid magnetic particle inspection standards, but usage is not limited to such applications. Except for carbon content and tensile properties this material is similar to AMS 6417.

Certain design and processing procedures may cause these products to become susceptible to stress-corrosion cracking after heat treatment; ARP 1110 recommends practices to minimize such conditions.